On the formation and structure of downdrafts in cumulus clouds

Abstract

Downdrafts, exhibiting speeds and mass transports comparable to those of the main updrafts, are a common feature of the cumulus clouds studied by the Woods Hole Oceanographic Institution's FBI aircraft in the trade-wind region. These downdrafts are observed to be most pronounced at the extreme downshear edge of the visible cloud and are generally stronger the greater the age of the cloud tower, although they are normally present at the edge of even rapidly growing turrets.